Beyerdynamic A20, with a 100-ohm output impedance (unusual for a SS h/p/a), is a tremendous match for Sennheiser HD660-S2. While discontinued, A20 can be found. I just purchased a second A20 - unused, new in box - for $435 USD “all in”.
Wow, such an interesting pairing. I always wanted to try that amp (or the A2) since I own both 660s2 and DT880 600 ohm.Beyerdynamic A20, with a 100-ohm output impedance (unusual for a SS h/p/a), is a tremendous match for Sennheiser HD660-S2. While discontinued, A20 can be found. I just purchased a second A20 - unused, new in box - for $435 USD “all in”.
Don't believe I'm about to win any popularity contests with my eclectic choice of music, but....
https://listen.tidal.com/album/8946138
George Crumb's "Music for a Summer Evening" was extremely well reproduced, the new driver IMHO has a quickness and dynamic character about it where even delicate percussion instrument emerge out of a blacker background and even when the piece moves into into it's more chaotic movements all instrumentation remains intact.
Timbre is all rather correct and the piano is spot on.
"The battery of percussion instruments required for Summer Evening is extensive and includes vibraphone,
xylophone, glockenspiel, tubular bells, crotales (antique cymbals), bell tree, claves,
maracas, sleighbells, wood blocks and temple blocks, triangles, and several varieties of
drums, tam-tams, and cymbals."
https://edisciplinas.usp.br/pluginfile.php/3068321/mod_resource/content/1/Music for a Summer Evening - program notes (George Crumb).pdf
I think you made the right choice. The HD660S2's have become some of my favourites. The 109's, not so much.
My 600, 660S and 660S2 all have mods. 600 has the CC mod, silk mesh inside the earcups and stock pads like all of Jonathan's 6 series. 660S has 650 capsule, silk mesh in the earcups, stock pads and 650 grilles. My 660S2 has only the ZMF fenestrated lambskin pads installed, no silk mesh or stock foam underneath the earpads, just the lining of the ZMF earpads, stock grills and capsule. I have done this type of ranking on different categories with respect to stock form, but this one is with regard to the aforementioned configs of the headphones so keep that in mind. Because of my modding idk how helpful this will be for you guys, but take what you can from this. I included the areas for comparison that matter most to me currently.
Re the following categories the pecking order is as follows:
Micro detail retrieval
660S2 > 600 > 660S
660S2 just digs out a little more fine (micro details) details than the 600. It's just a smidge but it makes a difference. 600 and 660S2 both do micro detail retrieval better than 660S imo. I feel there's been improvements to the ability to render all parts of the frequency range as it relates to the 660S2
Mids/Timbre:
600 > 660S2 > 660S
The King is still the King. 600 is the GOAT I've heard in terms of timbre. 660S2 is great too, but there's just something very life-like about the way the 600 presents the music. I don't know if it will ever be outdone. I think the 660S2 has a smidge more detail it's bringing in the midrange though, so it's a pick your poison kind of in this area and maybe they are a wash here. I'll put the 600 over it slightly because of it's unique presentation in the timbre department, and because it also presents midrange detail very well.
Staging:
660S2 > 660S > 600
The ZMF pads work really well to my ears with the 660S and the 660S2. They do not improve the 600 staging capabilities and mess with the tonality of the 600 too much imo. They have some magic synergy with the newer drivers though and beat the 600 in this department on all things staging wise. 660S2 has the ability to render 3 dimensional staging but not so much with the stock pads imo. It is capable of greater depth/width, imaging and layering than the 660S with the ZMF pads.
Bass textures (ability to perform different types of bass with accuracy):
660S2 > than both of the other models. I haven't decided between 600 and 600s.
Sennheiser made an improvement here that is undeniable. There's more actual details in the bass notes to be heard and it goes lower than the other two models. 600 is improved with the CC mod in this department. I heard the CC modded 600 slam harder than the 660S2 yesterday, but 660S2 is just better with presenting details of bass notes on the same track. 660S2 has a warmer tone generally than the 600. Senn has done their work in adding this warmth in the mid-bass whilst not making this such a hallmark character of the headphone, as with the 650. It sits between the CC modded 600 and 650 in terms of mid bass warmth with the ZMF pad mod imo. 600 is the most neutral of the three. 660S with the silk mesh sounds about as warm as the 660S2 with the ZMF pad mod to my ears. 660S is even warmer in stock form, which i don't like. 660S2 with silk mesh and stock pads was the coolest config in terms tonality to me, which I also did not like.
Treble detail/extension:
660S2 > 600 > 660S
There's just more treble that is helping 660S2 dig out a little more micro details than 600 and quite a bit more than 660S. It's still smooth as butter though. It has more treble in all three configs (stock foam and stock pads, w silk mesh and stock pads and ZMF fenestrated pads) than the other two.
Overall resolution:
660S2 > 600 > 660s
Again, the way these headphones are configured i have to give it to the 660S2. It just sounds like I'm not really missing anything. The improvements to the staging really adds so much to this headphone. I can't say it enough. W the stock pads in comparison to the 600 I heard better imaging, but similar height, width and depth (perhaps a hair more depth) between the two. The ZMF pads put the 660S2 in another category for me.
Dynamics:
600 > 660S2 > 660S
I will say also that I notice less difference difference between the ability of the 600 and 660S2 to render varied swings of notes regarding loudness in the mix when listening to classical. This is something I noted when I first owned 660S2, that notes sounded more uniform even where there should be a larger swing dynamically within a track that's gets portrayed accurately by the 600. I've noticed this difference less with this 660S2 that I now own. Maybe I heard it wrong months ago, or maybe it was unit variation, or maybe there was an improvement made?? Idk .. Senn has made revisions upon releases of headphones. They did it with the 660S which upon release was a bright headphone. Most of us know how it sounds now. It def ain't bright. That was not an accident or figment of imaginations lol. Either way this is an improvement that I will gladly take, but I still have 600 slightly ahead of the 660S2 in this regard.
That's all I have for now lol. Back to listening.
I'll just say lastly that i'm thankful for Senn's efforts on all of these headphones which have brought me so much enjoyment over the years.
Which one of these https://shop.zmfheadphones.com/collections/pads ideal for 660s2, the one you refer to in your post? Thanks.My 600, 660S and 660S2 all have mods. 600 has the CC mod, silk mesh inside the earcups and stock pads like all of Jonathan's 6 series. 660S has 650 capsule, silk mesh in the earcups, stock pads and 650 grilles. My 660S2 has only the ZMF fenestrated lambskin pads installed, no silk mesh or stock foam underneath the earpads, just the lining of the ZMF earpads, stock grills and capsule. I have done this type of ranking on different categories with respect to stock form, but this one is with regard to the aforementioned configs of the headphones so keep that in mind. Because of my modding idk how helpful this will be for you guys, but take what you can from this. I included the areas for comparison that matter most to me currently.
Re the following categories the pecking order is as follows:
Micro detail retrieval
660S2 > 600 > 660S
660S2 just digs out a little more fine (micro details) details than the 600. It's just a smidge but it makes a difference. 600 and 660S2 both do micro detail retrieval better than 660S imo. I feel there's been improvements to the ability to render all parts of the frequency range as it relates to the 660S2
Mids/Timbre:
600 > 660S2 > 660S
The King is still the King. 600 is the GOAT I've heard in terms of timbre. 660S2 is great too, but there's just something very life-like about the way the 600 presents the music. I don't know if it will ever be outdone. I think the 660S2 has a smidge more detail it's bringing in the midrange though, so it's a pick your poison kind of in this area and maybe they are a wash here. I'll put the 600 over it slightly because of it's unique presentation in the timbre department, and because it also presents midrange detail very well.
Staging:
660S2 > 660S > 600
The ZMF pads work really well to my ears with the 660S and the 660S2. They do not improve the 600 staging capabilities and mess with the tonality of the 600 too much imo. They have some magic synergy with the newer drivers though and beat the 600 in this department on all things staging wise. 660S2 has the ability to render 3 dimensional staging but not so much with the stock pads imo. It is capable of greater depth/width, imaging and layering than the 660S with the ZMF pads.
Bass textures (ability to perform different types of bass with accuracy):
660S2 > than both of the other models. I haven't decided between 600 and 600s.
Sennheiser made an improvement here that is undeniable. There's more actual details in the bass notes to be heard and it goes lower than the other two models. 600 is improved with the CC mod in this department. I heard the CC modded 600 slam harder than the 660S2 yesterday, but 660S2 is just better with presenting details of bass notes on the same track. 660S2 has a warmer tone generally than the 600. Senn has done their work in adding this warmth in the mid-bass whilst not making this such a hallmark character of the headphone, as with the 650. It sits between the CC modded 600 and 650 in terms of mid bass warmth with the ZMF pad mod imo. 600 is the most neutral of the three. 660S with the silk mesh sounds about as warm as the 660S2 with the ZMF pad mod to my ears. 660S is even warmer in stock form, which i don't like. 660S2 with silk mesh and stock pads was the coolest config in terms tonality to me, which I also did not like.
Treble detail/extension:
660S2 > 600 > 660S
There's just more treble that is helping 660S2 dig out a little more micro details than 600 and quite a bit more than 660S. It's still smooth as butter though. It has more treble in all three configs (stock foam and stock pads, w silk mesh and stock pads and ZMF fenestrated pads) than the other two.
Overall resolution:
660S2 > 600 > 660s
Again, the way these headphones are configured i have to give it to the 660S2. It just sounds like I'm not really missing anything. The improvements to the staging really adds so much to this headphone. I can't say it enough. W the stock pads in comparison to the 600 I heard better imaging, but similar height, width and depth (perhaps a hair more depth) between the two. The ZMF pads put the 660S2 in another category for me.
Dynamics:
600 > 660S2 > 660S
I will say also that I notice less difference difference between the ability of the 600 and 660S2 to render varied swings of notes regarding loudness in the mix when listening to classical. This is something I noted when I first owned 660S2, that notes sounded more uniform even where there should be a larger swing dynamically within a track that's gets portrayed accurately by the 600. I've noticed this difference less with this 660S2 that I now own. Maybe I heard it wrong months ago, or maybe it was unit variation, or maybe there was an improvement made?? Idk .. Senn has made revisions upon releases of headphones. They did it with the 660S which upon release was a bright headphone. Most of us know how it sounds now. It def ain't bright. That was not an accident or figment of imaginations lol. Either way this is an improvement that I will gladly take, but I still have 600 slightly ahead of the 660S2 in this regard.
That's all I have for now lol. Back to listening.
I'll just say lastly that i'm thankful for Senn's efforts on all of these headphones which have brought me so much enjoyment over the years.
Currently listening to Nine Inch Nails - The Downward Spiral while working (from home
Wonderful suggestion and for the reasons you lay out in particular.
Oh thanks a ton! Loving the S2 cans but human nature greed being a thing, wondering if there is a way to extend the soundstage, retaining all else with these. Oh well!
Does it extend the soundstage as detailed in his post? Hope so!
Yes they are, I find they sound very detailed. It's all I use
